Harappa, Bronze Age city of the Indus Valley civilization, also known as the Harappan civilization. It was built on artificial mounds on the left bank of a dried-up course of the Ravi, in eastern Pakistan, and was inhabited from c. 2500 to c. 1700 BC. The main features of the site, which include a fortified citadel, workers' quarters, areas for pounding grain, and buildings for storing it, all made of mudbrick or baked brick, suggest that it was an important centre for the control of food supplies. The fact that the site was systematically robbed of bricks for railway ballast and building material in the 19th century has made its reconstruction difficult; however, the layout of Harappa is very similar to that of Mohenjo-Daro, which is much better understood; inferences about Harappa have therefore been made on the basis of what is known about Mohenjo-Daro.